JP2010018733A - Cyclic polyarylene sulfide and method for producing it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cyclic polyarylene sulfide and a method for producing it having low crystallinity (heat of fusion of 20 J/g or less), or having no crystallinity substantially. <P>SOLUTION: A substantially amorphous cyclic polyarylene sulfide mixture containing 50 wt.% or more of a cyclic polyarylene sulfide is produced by heating a crystalline cyclic polyarylene sulfide mixture having heat of fusion above 20 J/g at a temperature of at least its heat of fusion and then cooling it. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cyclic polyarylene sulfide and a method for producing the same. More particularly, the present invention relates to a cyclic polyarylene sulfide having low crystallinity or substantially no crystallinity, and a method for producing the same.

  Aromatic cyclic compounds can be applied to highly functional materials and functional materials based on properties resulting from their cyclic properties, for example, properties as compounds with inclusion ability, and high molecular weight linear forms by ring-opening polymerization In recent years, it has attracted attention due to its specificity derived from its structure, such as its use as an effective monomer for polymer synthesis. Cyclic polyarylene sulfides (hereinafter, polyarylene sulfides may be abbreviated as PAS) typified by cyclic polyphenylene sulfides (hereinafter, polyphenylene sulfides may be abbreviated as PPS) are also included in the category of aromatic cyclic compounds. As mentioned above, it is a compound that is notable.

  As a method for producing a cyclic polyarylene sulfide, for example, a method in which a diaryl disulfide compound is oxidatively polymerized under ultradilution conditions has been proposed (see, for example, Patent Document 1). In this method, a method of obtaining cyclic PAS by dropping a reaction solution obtained after the reaction into methanol is disclosed, and cyclic hexa (thio-1,4-phenylene) (hereinafter, cyclic polyphenylene sulfide hexamer) is disclosed. Is sometimes obtained). The thermal characteristics of cyclic hexa (thio-1,4-phenylene), which is a cyclic polyarylene sulfide obtained by this method, are disclosed in Non-Patent Document 1, and according to this, this cyclic PAS is 209 ° C. Has a melting peak, and the heat of fusion is 46 J / g, which is disclosed to be extremely highly crystalline.

  As another method of obtaining a cyclic polyphenylene sulfide hexamer as a cyclic polyarylene sulfide, Soxhlet extraction is performed by extracting chloroform from a cross-linked polyphenylene sulfide (hereinafter sometimes referred to as PPS) resin with chloroform as an extraction solvent. A method of obtaining 99.9% pure cyclohexa (p-phenylene sulfide) as a white precipitate when the liquid is cooled to room temperature has been disclosed (for example, see Patent Document 2). As disclosed in Non-Patent Document 2, the thermal characteristics of the high-purity cyclic polyphenylene sulfide hexamer obtained by this method has an extremely high melting peak temperature of 348 ° C. Therefore, the heat of fusion is also 20 J / It is estimated that it greatly exceeds g. Regarding the thermal characteristics of the cyclic polyphenylene sulfide having a single number of repeating units, the cyclic polyphenylene sulfide tetramer, pentamer, heptamer, and octamer are each 296-298 ° C., 257- It has been disclosed to have extremely high melting peak temperatures of 259 ° C., 328 ° C., and 305 ° C. (see, for example, Non-Patent Documents 3 and 4). In general, it is known that the melting point of a homo-oligomer or homopolymer having the same repeating structure depends on the crystallinity, and the higher the melting point, the higher the heat of fusion. Here, the melting peak temperature of a general polyphenylene sulfide is about 280 ° C., and the heat of fusion is about 30 to 50 J / g. Therefore, the high melting peak temperature of the cyclic polyphenylene sulfide having the single repeating number is It can be said that these show extremely high crystallinity and the heat of fusion greatly exceeds 20 J / g. Further, such a cyclic PAS has a drawback that it is extremely difficult to melt.

  As another method for producing cyclic polyarylene sulfide, a method in which a copper salt of 4-bromothiophenol is heated under ultra-diluted conditions in quinoline is disclosed. In this method, after removing the solvent from the reaction solution obtained after the reaction, a concentrated solution of the product was obtained, and this was dropped into hydrous methanol, and then purified with aqueous hydrochloric acid and distilled water to recover the solid content. The chloroform-soluble matter of the solid content was recovered by reprecipitation using methanol, and the linear oligomer was dissolved and removed with ethyl acetate to obtain a cyclic polyphenylene sulfide oligomer. The cyclic polyphenylene sulfide oligomer obtained by this method is 20%, 40%, 20%, 20% of the polynuclear sulfide tetranuclear, 5-nuclear, hexanuclear, and higher nuclei, respectively. It is disclosed that the mixture has a melting point at 217 ° C. and the latent heat of fusion is 35.0 J / g (see, for example, Patent Document 3).

  Further, as a method for producing a mixture of cyclic polyarylene sulfides as described above, p-dichlorobenzene as a dihalogenated aromatic compound and sodium sulfide as an alkali metal sulfide are reacted in N-methylpyrrolidone which is an organic polar solvent. Next, after removing the solvent under heating and reduced pressure, the polyphenylene sulfide obtained by washing with water is extracted with methylene chloride, and the saturated solution of the extract obtained is reprecipitated in methanol to form a cyclic precipitate. A method for obtaining a phenylene sulfide oligomer mixture is disclosed (for example, see Patent Document 4). Although it is disclosed that a 7 to 15-mer cyclic phenylene sulfide oligomer mixture is obtained by this method, this method also includes the tetranuclear, pentanuclear, hexanuclear, and more of the above-mentioned cyclic polyphenylene sulfide. It is clear that the cyclic phenylene sulfide oligomer mixture is obtained using the same reprecipitation method as the mixture containing the number of nuclei, and this also has a high melting peak temperature and a heat of fusion exceeding 20 J / g. It is.

That is, the cyclic polyarylene sulfide obtained by the prior art has high crystallinity, has a high melting peak temperature and a heat of fusion exceeding 20 J / g, and requires a high temperature when melted and processed. It was a thing. This high processing temperature not only increases the generation gas and energy consumption during processing, but also when cyclic polyarylene sulfide is mixed with other materials such as engineering plastics typified by general-purpose plastics, polyamides and polyesters. The deterioration of these plastic materials can also be increased. Therefore, a cyclic polyarylene sulfide having low crystallinity, low melting peak temperature, and low heat of fusion has been desired.
Japanese Patent No. 3200027 (Claims) Japanese Patent Application Laid-Open No. 10-077408 (page 6) US Pat. No. 5,869,599 (page 14) JP 05-163349 A (page 7) macromolecules, vol.30, No.15, p.4503, 1997 Bull.Acad.Sci.USSR, 36, 8, p.1770 Tetrahedron Letters, vol.23, No.4, p.374 Bull.Acad.Sci., Vol.39, p.763-766, 1990

  An object of the present invention is to provide a cyclic polyarylene sulfide having a low crystallinity or substantially no crystallinity, and to provide a method for producing the same, which has solved the problems of the prior art.

In response to the above problems, the present invention
1. A cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide represented by the general formula (1), wherein the heating rate is 20 ° C. from 50 ° C. to 360 ° C. using a differential scanning calorimeter (DSC). A cyclic polyarylene sulfide characterized by having a heat of fusion of 20 J / g or less when measured at / min

(M is an integer of 4 to 50. m may be a mixture of 4 to 50)
2. The cyclic polyarylene sulfide according to item 1, wherein the content of cyclic PAS of m = 6 with respect to the cyclic polyarylene sulfide contained in the cyclic polyarylene sulfide mixture is less than 50% by weight,
3. When the total amount of cyclic polyarylene sulfides of general formula (1) where m is 4 to 12 in the cyclic polyarylene sulfides contained in the cyclic polyarylene sulfide mixture is 100%, m is a ring of 5 to 8 The cyclic polyarylene sulfide according to item 1 or 2, which contains 5% or more of each of the formula polyarylene sulfides,
4). Any one of Items 1 to 3, wherein the heat of fusion is 10 J / g or less when measured from a differential scanning calorimeter (DSC) from 50 ° C. to 360 ° C. at a heating rate of 20 ° C./min. A cyclic polyarylene sulfide according to claim 1,
5). Any one of Items 1 to 3, wherein a melting peak is substantially not observed when a differential scanning calorimeter (DSC) is measured from 50 ° C. to 360 ° C. at a heating rate of 20 ° C./min. A cyclic polyarylene sulfide according to claim 1,
6). A cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide represented by the general formula (1), wherein the temperature rising rate is 50 ° C. to 360 ° C. with a differential scanning calorimeter (DSC) 20 Any one of Items 1 to 5, wherein the cyclic polyarylene sulfide mixture having a heat of fusion of more than 20 J / g when measured at ° C / min is heated to a temperature higher than its melting peak temperature and then cooled. A process for producing the cyclic polyarylene sulfide according to claim 1,
7). The method for producing a cyclic polyarylene sulfide according to item 6, wherein the reduction rate of the cyclic polyarylene sulfide content contained in the cyclic polyarylene sulfide mixture is 10% or less before and after heating,
8). The method for producing a cyclic polyarylene sulfide according to claim 6 or 7, wherein an upper limit temperature of heating is 320 ° C or lower.

  According to the present invention, it is possible to provide a cyclic polyarylene sulfide having a low crystallinity and / or a cyclic polyarylene sulfide having substantially no crystallinity and a method for producing the same.

  Embodiments of the present invention will be described below.

(1) Cyclic polyarylene sulfide The polyarylene sulfide of the present invention is a cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide represented by the following formula (A), and is a differential scanning calorimeter. (DSC) is a cyclic polyarylene sulfide having a heat of fusion of 20 J / g or less when measured from 50 ° C. to 360 ° C. at a rate of temperature increase of 20 ° C./min.

  Here, the cyclic polyarylene sulfide in the present invention will be described in more detail. The cyclic polyarylene sulfide is a cyclic compound having a repeating unit of the formula — (Ar—S) — as a main constituent unit, and preferably 80 mol% of the repeating unit. It is a compound like the following general formula (A) contained above.

  Here, examples of Ar can include units represented by formula (B) to formula (M), among which formula (B) to formula (D) are preferable, and formula (B) and formula (C) are more preferable. The formula (B) is particularly preferred.

(In the formula, R1 and R2 are substituents selected from hydrogen, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and a halogen group, and R1 and R2 are the same or different. May be good.)

  In the cyclic polyarylene sulfide, the repeating units such as the above formulas (B) to (M) may be included at random, may be included as a block, or may be any mixture thereof. Typical examples of these include cyclic polyphenylene sulfide, cyclic polyphenylene sulfide sulfone, cyclic polyphenylene sulfide ketone, cyclic random copolymers containing these, cyclic block copolymers, and mixtures thereof. . Particularly preferred cyclic polyarylene sulfides include p-phenylene sulfide units as the main structural unit.

Is a cyclic polyphenylene sulfide containing 80 mol% or more, particularly 90 mol% or more (hereinafter sometimes abbreviated as cyclic PPS).

  The cyclic number m in the formula (A) of the cyclic polyarylene sulfide is 4 to 50, preferably 4 to 25, and more preferably 4 to 20. Since cyclic PAS in which m is in such a range tends to lower the fluidizing temperature when heated, the processing temperature is lowered when molding cyclic PAS or when melt-kneading with other resins. It is advantageous from the viewpoint of being able to do it. In addition, as m increases, the properties of cyclic polyarylene sulfides tend to resemble those of linear polyarylene sulfides described later. Cyclic polyarylene sulfides with large m are more crystalline than those with small m. It becomes easy to change. Therefore, in order to obtain a cyclic polyarylene sulfide having a heat of fusion of 20 J / g or less, which is a feature of the present invention, m is preferably in the above range. The cyclic polyarylene sulfide of the present invention may be either a single compound having a single repeating number or a mixture of cyclic polyarylene sulfides having different repeating numbers, but the cyclic polyarylene sulfide having different repeating numbers. This mixture is preferred because it has a lower melting solution temperature and lower heat of fusion than a single compound having a single repeating number.

  The cyclic polyarylene sulfide of the present invention is a cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide represented by the formula (A), preferably 70% by weight or more, more preferably Contains 80% by weight or more. The upper limit of the cyclic polyarylene sulfide contained in the cyclic polyarylene sulfide mixture is not particularly limited, but 98% by weight or less can be exemplified as a preferable range. Here, the compound other than the cyclic polyarylene sulfide in the cyclic polyarylene sulfide mixture is particularly preferably a linear polyarylene sulfide described later.

  As described above, the cyclic polyarylene sulfide of the present invention is a cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide, and the cyclic polyarylene sulfide contained in the cyclic polyarylene sulfide mixture is not limited. The content of cyclic PAS of m = 6 in formula (A) relative to the total amount is preferably less than 50% by weight, more preferably less than 40% by weight, and even more preferably less than 30% by weight (ring of m = 6). Formula PAS (weight) / (Cyclic PAS mixture (weight) × 100) The method disclosed in Patent Document 2 described above, that is, Soxhlet extraction of cross-linked PPS, and cooling the resulting extract In the method of obtaining a solid content, that is, the method of obtaining cyclic PPS by “recrystallization”, cyclohexa (p-phenol) having a purity of 99.9% is obtained. (Len sulfide) (cyclic PPS with m = 6) is disclosed, according to Non-Patent Document 2, this cyclic PPS has a melting peak temperature at 348 ° C. It is considered that this cyclic PPS of m = 6 has a very stable crystal structure and is easy to crystallize, and the heat of fusion greatly exceeds 20 J / g, reflecting this stable crystal structure. It is clear from Non-Patent Documents 3 and 4 that such a tendency can be applied to a single cyclic PPS other than m = 6, and therefore, when processing such a cyclic PAS, an extremely high processing temperature is obtained. In view of the fact that the melt processing temperature in the cyclic PAS production method to be described later can be lowered, the cyclic PAS mixture of the present invention particularly has a cyclic formula of m = 6 in the formula (A). PAS content Similarly, from the viewpoint that the melt processing temperature in the cyclic PAS production method described later can be lowered, cyclic polyarylene having a different number of repetitions as cyclic PAS is used in the present invention. As described above, it is preferable to use a mixture of sulfides. Of the cyclic PAS contained in the cyclic PAS mixture, the total amount of cyclic PAS in which m in the formula (A) is 4 to 12 is 100%. In this case, it is preferable to use a cyclic PAS mixture containing 5% or more of cyclic PAS each having 5 to 8 m, and using a cyclic PAS mixture containing 7% or more of cyclic PAS having 5 to 8 m. A cyclic PAS mixture having such a composition ratio is particularly preferred from the viewpoint of melt processability since it tends to have a low melting peak temperature and a low heat of fusion. . Here, the content of cyclic PAS having a different number of repetitions m relative to the total amount of cyclic polyarylene sulfide in the cyclic PAS mixture is determined when the cyclic PAS mixture is divided into components by high performance liquid chromatography equipped with a UV detector. The ratio of the peak area attributed to the cyclic PAS alone having the desired m number to the total peak area attributed to cyclic PAS. In addition, the qualitative characteristics of each peak divided into components by this high performance liquid chromatography can be obtained by separating each peak by preparative liquid chromatography and performing an absorption spectrum or mass analysis in infrared spectroscopic analysis.

  The feature of the cyclic polyarylene sulfide of the present invention is that the heat of fusion when the cyclic polyarylene sulfide is measured from 50 ° C. to 360 ° C. at a heating rate of 20 ° C./min with a differential scanning calorimeter (DSC) is 20 J / It is a cyclic polyarylene sulfide having g or less, preferably having a heat of fusion of 10 J / g or less, and more preferably having substantially no melting peak. In the present invention, even if a minute melting peak is detected, if the heat of fusion is 1 J / g or less, it is considered that the melting peak is not substantially recognized. In general, when an endothermic peak is observed when a solid substance is heated by DSC at room temperature, it can be interpreted that the substance to be measured has transitioned from the solid state to the liquid state, that is, melted in the vicinity of the endothermic peak temperature. It can be interpreted that the crystal structure formed at or below the melting peak became amorphous when the crystal structure was at or above the melting peak temperature. Further, the amount of heat required for melting, that is, the amount of heat of fusion is calculated from the area of the endothermic peak. Here, the cyclic arylene sulfide represented by the cyclic polyphenylene sulfide produced by the prior art has a melting peak temperature of 200 ° C. or higher in the above DSC measurement because it forms a crystal structure in the solid state. It is known that the heat of fusion exceeds 20 J / g. Such a cyclic arylene sulfide is present in an unmelted solid form in whole or in part below the melting peak temperature. Accordingly, a uniform composition cannot be obtained at a temperature lower than the melting peak temperature. For example, when the composition is mixed with another component (for example, a resin) that can take a uniform state at a temperature lower than the melting peak temperature of the cyclic arylene sulfide, a uniform composition is obtained. Will not be obtained. On the other hand, the cyclic arylene sulfide of the present invention has a heat of fusion of 20 J / g or less, preferably a heat of fusion of 10 J / g or less, and more preferably a cyclic arylene sulfide having substantially no melting peak at a low temperature. Since it can take a uniform state, it has the feature that it is easy to obtain a uniform composition with other components. More specifically, the cyclic arylene sulfide of the present invention is amorphous, and exhibits fluidity at a temperature exceeding the glass transition temperature, and thus has a feature that it can take a uniform state at an extremely low temperature. Here, for example, since the glass transition temperature of cyclic polyphenylene sulfide having paraphenylene sulfide as a structural unit exists in 70 to 100 ° C., it has an excellent feature of exhibiting fluidity above this temperature.

(2) Linear polyarylene sulfide The linear polyarylene sulfide in the present invention is a line containing a repeating unit of the formula, — (Ar—S) —, as the main constituent unit, preferably containing 80 mol% or more of the repeating unit. A linear homopolymer or a linear copolymer, and Ar includes units represented by the above formulas (B) to (M), among which the formula (B) to the formula (D) are preferable. (B) and formula (C) are more preferred, and formula (B) is particularly preferred.

  As long as this repeating unit is a main structural unit, it can contain a small amount of branching units or crosslinking units represented by the following formulas (N) to (Q). The amount of copolymerization of these branched units or cross-linked units is preferably in the range of 0 to 1 mol% with respect to 1 mol of-(Ar-S)-units.

  Further, the linear PAS in the present invention may be any of a random copolymer, a block copolymer and a mixture thereof containing the above repeating unit.

  Typical examples of these include polyphenylene sulfide, polyphenylene sulfide sulfone, polyphenylene sulfide ketone, random copolymers thereof, block copolymers, and mixtures thereof. Particularly preferred PASs include p-phenylene sulfide units as the main structural unit of the polymer.

In addition to polyphenylene sulfide (hereinafter sometimes abbreviated as PPS) containing 80 mol% or more, particularly 90 mol% or more, polyphenylene sulfide sulfone and polyphenylene sulfide ketone.

  The melt viscosity of various linear PASs in the present invention is not particularly limited, but the melt viscosity of a general linear PAS can be exemplified by a range of 0.01 to 1000 Pa · s (300 ° C., shear rate 1000 / sec). The range of 0.01 to 500 Pa · s is a preferable range from the viewpoint of availability. Moreover, there is no restriction | limiting in particular in the molecular weight of linear PAS, As a weight average molecular weight of general PAS, 200-1,000,000 can be illustrated. As described above, it is particularly preferable that the compound other than the cyclic polyarylene sulfide in the cyclic polyarylene sulfide mixture of the present invention is a linear polyarylene sulfide. The PAS preferably has a molecular weight of 200 to 5,000, particularly preferably 300 to 2,500. Since this preferred molecular weight linear PAS has a characteristic that it is difficult to take a crystal structure because the molecular weight is smaller than that of a normal linear PAS, even if such a linear PAS is included in a cyclic PAS mixture, It tends to be easy to obtain a cyclic PAS having a heat of fusion of 20 J / g or less, which is a characteristic of the above.

  The production method of such a linear PAS is not particularly limited, and any production method can be used. For example, Japanese Patent Publication No. 45-3368, Japanese Patent Publication No. 52-12240, Japanese Patent Publication No. 63 A method of reacting an aromatic compound or thiophene containing at least one nucleus-substituted halogen and an alkali metal monosulfide at an elevated temperature in a polar organic polar solvent, represented by JP-3375, preferably sulfidation It can be obtained by contacting an agent and a dihalogenated aromatic compound in an organic polar solvent.

  In general, the production of a cyclic compound is a competitive reaction between the production of a cyclic compound as a target product and the production of a linear compound. Therefore, in the method for the production of cyclic PAS, the ring of the target product is produced. In addition to the formula PAS, linear PAS is produced as a by-product. Therefore, when trying to obtain a cyclic PAS, there is a tendency that a linear PAS as a by-product is mixed. Here, in order to isolate only the cyclic PAS, it is often necessary to control extremely strict purification conditions, and even if it can be isolated, as disclosed in Non-Patent Documents 1 to 4 described above, Its crystallinity is extremely high and a cyclic PAS having a high melting point tends to be obtained. On the other hand, the cyclic PAS used in the present invention may be a mixture containing 50% or more of cyclic PAS, and such a mixture can be said to be an advantageous method from the viewpoint that extremely strict purification conditions are not required.

(3) Method for Producing Cyclic Polyarylene Sulfide The cyclic polyarylene sulfide of the present invention has a heat of fusion when measured at a heating rate of 20 ° C./min from 50 ° C. to 360 ° C. with a differential scanning calorimeter (DSC). Is 20 J / g or less, preferably the heat of fusion is 10 J / g or less, more preferably substantially no melting peak is observed. Such a cyclic polyarylene sulfide is, for example, A cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide represented by (A), wherein the temperature rise rate is 20 ° C./min from 50 ° C. to 360 ° C. with a differential scanning calorimeter (DSC). The cyclic polyarylene sulfide mixture having a heat of fusion of more than 20 J / g as measured by (1) was heated above its melting peak temperature and then cooled. Can be built.

  More preferable heating temperature in the production of the cyclic PAS of the present invention is preferably a temperature that is 20 ° C. or more higher than the melting peak temperature of the cyclic PAS mixture used as a raw material, more preferably a temperature that is 30 ° C. or higher, and a temperature that is 40 ° C. or higher. More preferably, for example, when the melting peak is broad, it can be said that it is a preferable method to employ a temperature higher by 50 ° C. or more. Here, the melting peak temperature of the cyclic PAS mixture used as a raw material can be estimated by the above-mentioned DSC measurement, but generally the melting temperature has a range, and the endotherm accompanying melting tends to continue even above the peak temperature. In order to dissolve uniformly, it is desirable to employ the preferable heating temperature. Moreover, since the upper limit temperature in heating also depends on the time for heating, it cannot be uniquely limited, but is preferably 320 ° C. or lower, more preferably 300 ° C. or lower, and further preferably 290 ° C. or lower. Below this preferred upper limit temperature, the cyclic PAS is unlikely to deteriorate during heating. The reaction may be a one-step reaction performed at a constant temperature, a multi-step reaction in which the temperature is raised stepwise, or a reaction in which the temperature is continuously changed.

  Further, the heating time depends on the composition of the cyclic PAS mixture of raw materials used, the melting peak temperature, the heat of fusion, and the amount of these raw materials or the heating temperature. Is more preferable. On the other hand, the upper limit of the heating time is preferably within 30 minutes, more preferably within 20 minutes. By setting this preferable time, the cyclic PAS as a raw material can be uniformly dissolved, and the cyclic PAS during heating tends to be hardly deteriorated. Further, it is preferable that no components other than the raw material cyclic PAS are present during heating. For example, it is desirable to perform heating in the absence of various solvents.

  The raw cyclic PAS is heated, preferably melted to obtain a uniform melt, and then cooled to obtain a cyclic PAS having a heat of fusion of 20 J / g or less. Here, the cooling is preferably performed to a temperature at which the cyclic PAS is in a solid state, and the obtained cyclic PAS is easily recovered. Here, the cooling is preferably performed to the glass transition temperature or lower of the cyclic PAS, specifically, preferably cooled to 100 ° C. or lower, more preferably 70 ° C. or lower, and further preferably 50 ° C. or lower. . By cooling to below this preferred temperature, the cyclic PAS becomes a solid, and the subsequent recovery operation becomes easy. Although there is no particular limitation on the cooling method, a method of forcibly cooling the cyclic PAS melt at a constant speed, a method of naturally cooling, a melt is discharged into water near room temperature, for example, and rapidly cooled to near room temperature. A method etc. can be illustrated. When the cyclic PAS used here is easily crystallized, a method of quenching is preferred, but the preferred cyclic PAS in the present invention described above (for example, the composition of the repeating unit m in the formula (A)) is When cooling from the melt, the crystal structure tends to be difficult to take, and therefore it is not always necessary to perform rapid cooling.

  The production method of the cyclic PAS, that is, the operation from the series of heating to cooling, can employ a known method such as a batch method and a continuous method. Further, the atmosphere in the production is preferably a non-oxidizing atmosphere, and it is preferably performed under an inert gas atmosphere such as nitrogen, helium, and argon, or under reduced pressure conditions, particularly from the viewpoint of economy and ease of handling. A nitrogen atmosphere or a reduced pressure condition is preferred.

  In the production of the cyclic PAS of the present invention, a cyclic PAS mixture (hereinafter sometimes referred to as cPAS1) having a heat of fusion of more than 20 J / g is used as a raw material and heated after its melting peak temperature or higher and then cooled. A cyclic PAS mixture (hereinafter sometimes referred to as cPAS2) having a heat of fusion of 20 J / g or less is obtained, but the reduction rate of the cyclic PAS content contained in the cyclic PAS mixture before and after this heating is 10% or less. It is preferably 5% or less. That is, when the cyclic PAS content contained in the raw material cPAS1 is 100%, the cyclic PAS content contained in the cPAS2 obtained after heating is preferably more than 90%, more preferably more than 95%. . By the way, as one of the applications of cyclic PAS, it can be exemplified that linear PAS is obtained by ring-opening polymerization of cyclic PAS. As a result of the present inventors' extensive investigation on the behavior of ring-opening polymerization, It has been found that ring-opening polymerization proceeds by heating the formula PAS. Here, in the method for producing the cyclic PAS of the present invention, the raw material cPAS1 is heated. When this heating temperature is a temperature at which the ring-opening polymerization of the cyclic PAS proceeds, one of the cyclic PASs contained in the raw material cPAS1 is used. In some cases, the cyclic PAS contained in the cPAS2 obtained after heating and cooling is reduced compared with the starting material cPAS1. In this case, linear PAS produced by ring-opening polymerization of cyclic PAS has a strong tendency to become a high molecular weight polymer having a weight average molecular weight of 10,000 or more, and tends to have a property greatly different from that of cyclic PAS. For example, when the cyclic PAS is a cyclic PPS, a high molecular weight linear PPS is produced by ring-opening polymerization. Since high molecular weight linear PPS is a crystalline resin having a high melting point and excellent chemical resistance, when such linear PPS is contained in cyclic PAS, it is not yet possible to melt cyclic PAS. It may remain as a melt or may remain as an undissolved material when cyclic PAS is dissolved in a solvent. Therefore, from the viewpoint of avoiding ring-opening polymerization due to heating of such cyclic PAS, the preferred temperature range for heating cPAS1 is desirable, and the reduction rate of cyclic PAS content after heating of cPAS1 is 10%. The following is desirable.

  Here, the cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide used as the raw material of the polyarylene sulfide of the present invention may be one having a heat of fusion exceeding 20 J / g. There is no particular limitation on the method for preparing such a cyclic polyarylene sulfide. For example, it is possible to use the cyclic polyarylene sulfide obtained by the prior art described above, and it is possible to use a single compound having a single number of repetitions or different repetitions. Any of the mixtures of cyclic polyarylene sulfides having a number can be used, but can also be obtained by the following method disclosed in, for example, International Publication No. WO2007 / 034800.

  (A) Granules separated by 80 mesh sieve (aperture 0.125 mm) by polymerizing polyarylene sulfide resin by heating a mixture containing at least a polyhalogenated aromatic compound, a sulfidizing agent and an organic polar solvent A mixture containing a PAS resin, a PAS component produced by polymerization and other than the granular PAS resin (referred to as polyarylene sulfide oligomer), an organic polar solvent, water, and an alkali metal halide salt; A method of obtaining a cyclic PAS mixture by separating and recovering the polyarylene sulfide oligomer contained therein and subjecting it to a purification operation.

(B) heating a mixture containing at least a polyhalogenated aromatic compound, a sulfidizing agent and an organic polar solvent to polymerize a polyarylene sulfide resin, and removing the organic polar solvent by a known method after the completion of the polymerization; A PAS resin containing cyclic PAS obtained by preparing a mixture containing polyarylene sulfide resin, water, and an alkali metal halide salt and purifying the mixture by a known method is obtained. In which cyclic PAS is extracted by using a solvent that does not dissolve, but cyclic PAS is recovered.
(4) Use of cyclic polyarylene sulfide of the present invention (a) Resin composition containing the cyclic PAS of the present invention

  Since the cyclic PAS of the present invention has excellent characteristics as shown in the above (1), it can be easily blended with various resins. A resin composition containing such a cyclic PAS has a strong tendency to exhibit excellent fluidity at the time of melt processing, and also tends to have excellent residence stability. Such improved properties, particularly fluidity, express the characteristics of excellent melt processability even when the heating temperature during melt processing of the resin composition is low, so that extrusion molding of injection molded products, fibers, films, etc. This is a great merit in that it improves the melt processability when processed into a product. The reason why such improvement in properties is manifested when cyclic PAS is blended is not clear, but because of the specificity of cyclic PAS structure, that is, the cyclic structure, it is compact compared to ordinary linear compounds. It is assumed that the entanglement with various resins that are matrixes tends to be reduced, that it acts as a plasticizer for various resins, and that the entanglement between matrix resins is also suppressed. .

  Although there is no restriction | limiting in particular in the compounding quantity at the time of mix | blending cyclic PAS with various resin, 0.1-50 weight part of cyclic PAS of this invention is preferable with respect to 100 weight part of various resin, Preferably it is 0.5-20. By blending parts by weight, more preferably 0.5 to 10 parts by weight, it is possible to obtain a remarkable improvement in characteristics.

  Moreover, it is also possible to mix | blend a fibrous and / or non-fibrous filler with the said resin composition as needed, The compounding quantity is 0.5 to 100 weight part of said various resin. A range of 400 parts by weight, preferably 0.5 to 300 parts by weight, more preferably 1 to 200 parts by weight, and even more preferably 1 to 100 parts by weight can be exemplified, and thereby mechanical strength while maintaining excellent fluidity. Tends to be improved. As the kind of filler, any filler such as fibrous, plate-like, powdery, and granular can be used. Preferable specific examples of these fillers include glass fibers, talc, wollastonite, and layered silicates such as montmorillonite and synthetic mica, with glass fibers being particularly preferable. The type of glass fiber is not particularly limited as long as it is generally used for reinforcing a resin, and can be selected from, for example, a long fiber type, a short fiber type chopped strand, a milled fiber, or the like. Moreover, said filler can also be used in combination of 2 or more types. The surface of the filler used in the present invention can also be used by treating the surface with a known coupling agent (for example, silane coupling agent, titanate coupling agent, etc.) or other surface treatment agents. . The glass fiber may be coated or bundled with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin.

  Moreover, in order to maintain the thermal stability of the resin composition, it is possible to include one or more heat-resistant agents selected from phenolic and phosphorus compounds. The blending amount of the heat-resistant agent is preferably 0.01 parts by weight or more, particularly preferably 0.02 parts by weight or more with respect to 100 parts by weight of the various resins from the viewpoint of heat resistance improvement effect. From this viewpoint, it is preferably 5 parts by weight or less, particularly preferably 1 part by weight or less. In addition, it is particularly preferable to use a phenolic compound and a phosphorus compound in combination because of their large heat resistance, heat stability, and fluidity retention effect.

  Further, the resin composition includes the following compounds, that is, coupling agents such as organic titanate compounds and organic borane compounds, polyalkylene oxide oligomer compounds, thioether compounds, ester compounds, and organic phosphorus compounds. Plasticizers such as talc, kaolin, organophosphorus compounds, polyether ether ketone and other crystal nucleating agents, montanic acid waxes, metal soaps such as lithium stearate and aluminum stearate, ethylenediamine, stearic acid and sebacic acid heavy compounding Normal additives such as lubricants, mold release agents such as silicone compounds, anti-coloring agents such as hypophosphite, and other lubricants, UV inhibitors, coloring agents, flame retardants, and foaming agents. . All of the above compounds tend to exhibit their effects effectively when added in an amount of less than 20 parts by weight, preferably 10 parts by weight or less, more preferably 1 part by weight or less, based on 100 parts by weight of the various resins.

  The method for producing the resin composition comprising the cyclic PAS as described above is not particularly limited. For example, the cyclic PAS, various resins, and other fillers and various additives as necessary may be added in advance. After blending, at a temperature higher than the fluidization temperature of various resins and cyclic PAS, a method of melt kneading with a generally known melt mixer such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader, or a mixing roll, after mixing in a solution A method of removing the solvent is used. Here, since the cyclic PAS of the present invention has a feature of low heat of fusion and low crystallinity, it can be fluidized at a temperature significantly lower than that of the known cyclic PAS. It can be said that this is a particularly preferable feature.

  Here, there are no particular limitations on the various resins in which the cyclic PAS is blended, and application to thermoplastic resins such as crystalline resins and amorphous resins, and thermosetting resins is also possible.

  Specific examples of the crystalline resin include, for example, polyolefin resins such as polyethylene resin, polypropylene resin, and syndiotactic polystyrene, polyvinyl alcohol resin, polyvinylidene chloride resin, polyester resin, polyamide resin, polyacetal resin, polyphenylene sulfide resin, Examples include polyetheretherketone resins, polyetherketone resins, polyketone resins, polyimide resins, and copolymers thereof, which may be used alone or in combination of two or more. Of these, polyphenylene sulfide resins, polyamide resins, and polyester resins are preferable in terms of heat resistance, moldability, fluidity, and mechanical properties. Moreover, a polyester resin is preferable from the viewpoint of transparency of the obtained molded product. When a crystalline resin is used as the various resins, there is a tendency to improve the crystallization characteristics in addition to the improvement in fluidity described above. In addition, it is particularly preferable to use polyphenylene sulfide resin as various resins. In this case, it is said that the improvement of the crystallinity and the effect of these effects are significantly suppressed in the injection molding as well as the fluidity. Features tend to develop easily.

  The amorphous resin is not particularly limited as long as it is an amorphous resin that can be melt-molded. However, in terms of heat resistance, the glass transition temperature is preferably 50 ° C. or higher, and is 60 ° C. or higher. Is more preferable, it is more preferable that it is 70 degreeC or more, and it is especially preferable that it is 80 degreeC or more. The upper limit is not particularly limited, but is preferably 300 ° C. or less, more preferably 280 ° C. or less from the viewpoint of moldability. In the present invention, the glass transition temperature of the amorphous resin is determined by increasing the temperature of the amorphous resin from 30 ° C. to the predicted glass transition temperature or higher in the differential calorimetry at 20 ° C./min. The glass transition temperature (Tg) observed when the temperature is measured again under the temperature rising condition at 20 ° C./min after holding for 1 minute, once cooling to 0 ° C. under the temperature lowering condition at 20 ° C./min, holding for 1 minute. Point to. Specific examples thereof include amorphous nylon resin, polycarbonate (PC) resin, polyarylate resin, ABS resin, poly (meth) acrylate resin, poly (meth) acrylate copolymer, polysulfone resin, and polyethersulfone resin. At least one kind may be exemplified, and one kind or two or more kinds may be used in combination. Among these amorphous resins, polycarbonate (PC) resin having particularly high transparency, and among ABS resins, transparent ABS resin, polyarylate resin, poly (meth) acrylate resin, and poly (meth) acrylate copolymer, polyether A sulfone resin can be preferably used. When an amorphous resin is used as various resins, in addition to the improvement in fluidity at the time of melt processing described above, high transparency can be maintained when an amorphous resin having excellent transparency is used. The characteristics that can be expressed. Here, when it is desired to develop high transparency in the amorphous resin composition, it is preferable to use a cyclic PAS having a heat of fusion of 10 J / g or less, more preferably a melting peak is substantially recognized. It is preferable to use those that cannot be used. By using such a cyclic PAS, the cyclic PAS is easily melt-dispersed when melt-kneaded with an amorphous resin, so that aggregates in the resin tend to be reduced or transparency is improved. Therefore, it is effective.

  The resin composition obtained by blending cyclic PAS with various resins obtained above can be molded by any known method such as injection molding, extrusion molding, blow molding, press molding, spinning, etc. Can be processed and used. As molded products, they can be used as injection molded products, extrusion molded products, blow molded products, films, sheets, fibers, and the like. The various molded articles thus obtained can be used for various applications such as automobile parts, electrical / electronic parts, building members, various containers, daily necessities, household goods and sanitary goods. Moreover, the said resin composition and a molded article consisting thereof can be recycled. For example, a resin composition obtained by pulverizing a resin composition and a molded product comprising the resin composition, preferably in a powder form, and then adding additives as necessary, can be used in the same manner as the resin composition described above. It can also be a molded product.

(B) Conversion of cyclic PAS to a high degree of polymerization The cyclic PAS produced according to the present invention has excellent characteristics as described in (1), so that as a prepolymer when obtaining a polymer by ring-opening polymerization It can be suitably used. The prepolymer here includes at least the cyclic polyarylene sulfide of the present invention, which can be converted into a high degree of polymerization of polyarylene sulfide by the method exemplified below, that is, a prepolymer of polyarylene sulfide. Hereinafter, it may be referred to as a PAS prepolymer.

  The ring-opening polymerization of the cyclic PAS may be carried out under conditions where the ring-opening of the cyclic PAS occurs and a high molecular weight product is formed. For example, the PAS prepolymer containing the cyclic PAS of the present invention is heated to obtain a high degree of polymerization. A preferable method is a method of conversion into a cis. The heating temperature is preferably equal to or higher than the temperature at which the PAS prepolymer is fluidized, and there is no particular limitation as long as such temperature conditions are satisfied. When the heating temperature is equal to or higher than the fluidization temperature of the PAS prepolymer, a PAS having a high molecular weight tends to be easily obtained in a short time. Note that the temperature at which the PAS prepolymer fluidizes varies depending on the composition and molecular weight of the PAS prepolymer and the environment during heating, and therefore cannot be uniquely indicated. For example, the PAS prepolymer is a differential scanning calorimeter. It is possible to grasp by analyzing with a viscoelasticity measuring machine represented by a rheometer. If the heating temperature is too high, undesirable side reactions such as cross-linking reactions and decomposition reactions between PAS prepolymers, between PASs produced by heating, and between PAS and polyarylene sulfide prepolymers tend to occur. Therefore, it is desirable to avoid a temperature at which such an undesirable side reaction is prominent because the properties of the obtained PAS may deteriorate. Examples of the heating temperature at which the manifestation of such undesirable side reactions can be suppressed include 100 to 400 ° C, preferably 150 to 380 ° C, more preferably 200 to 360 ° C. On the other hand, if there is no problem even if a certain degree of side reaction occurs, a temperature range of 250 to 450 ° C., preferably 280 to 420 ° C., can be selected. There is an advantage that can be performed.

  The heating time cannot be uniformly defined because it varies depending on various properties such as cyclic PAS content, m number, and molecular weight in the PAS prepolymer to be used, and conditions such as the heating temperature. It is preferable to set so that undesirable side reactions do not occur as much as possible. Examples of the heating time include 0.05 to 100 hours, preferably 0.1 to 20 hours, and more preferably 0.1 to 10 hours. If the time is less than 0.05 hours, the conversion of the PAS prepolymer to PAS tends to be insufficient, and if the time exceeds 100 hours, the possibility of adverse effects on the properties of the resulting PAS due to undesirable side reactions tends to become obvious. Not only that, but there may be economic disadvantages.

  The PAS prepolymer can also contain various catalyst components that promote conversion when converted to a high degree of polymerization by heating. Examples of such catalyst components include ionic compounds and compounds having radical generating ability. Examples of the ionic compound include sulfur alkali metal salts such as thiophenol sodium salt and lithium salt, and examples of the compound capable of generating radicals include compounds capable of generating sulfur radicals upon heating. Specific examples include compounds containing a disulfide bond. When various catalyst components are used, the catalyst component is usually taken into PAS, and the obtained PAS often contains the catalyst component. In particular, when an ionic compound containing an alkali metal and / or other metal component is used as a catalyst component, most of the metal component contained therein tends to remain in the obtained PAS. In addition, PAS obtained using various catalyst components tends to increase in weight loss when PAS is heated. Therefore, when a higher purity PAS is desired and / or when a PAS with less weight loss when heated is desired, it is desirable to use as little as possible, preferably not, a catalyst component. Therefore, when converting the PAS prepolymer to a high degree of polymerization using various catalyst components, the amount of alkali metal in the reaction system containing the PAS prepolymer and the catalyst component is 100 ppm or less, preferably 50 ppm or less, more preferably Is 30 ppm or less, more preferably 10 ppm or less, and the disulfide weight based on the total sulfur weight in the reaction system is less than 1 wt%, preferably less than 0.5 wt%, more preferably less than 0.3 wt%, More preferably, the addition amount of the catalyst component is adjusted so as to be less than 0.1% by weight.

  The conversion of the PAS prepolymer to a high degree of polymerization by heating is usually carried out in the absence of a solvent, but can also be carried out in the presence of a solvent. The solvent is not particularly limited as long as it does not substantially cause undesirable side reactions such as inhibition of conversion to a high degree of polymerization by heating of the PAS prepolymer and decomposition or crosslinking of the produced PAS. Nitrogen-containing polar solvents such as methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, sulfoxide / sulfone solvents such as dimethyl sulfoxide, dimethyl sulfone, ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, acetophenone, dimethyl ether, dipropyl ether , Ether solvents such as tetrahydrofuran, halogen solvents such as chloroform, methylene chloride, trichloroethylene, ethylene chloride, dichloroethane, tetrachloroethane, chlorobenzene, methanol, ethanol, propylene Lumpur, butanol, pentanol, ethylene glycol, propylene glycol, phenol, cresol, alcohol phenol based solvents such as polyethylene glycol, benzene, toluene, and aromatic hydrocarbon solvents such as xylene. It is also possible to use an inorganic compound such as carbon dioxide, nitrogen, or water as a solvent in a supercritical fluid state. These solvents can be used as one kind or a mixture of two or more kinds.

  The conversion of the PAS prepolymer to a high degree of polymerization by heating may be performed in a mold for producing a molded product, as well as by a method using a normal polymerization reaction apparatus, an extruder, Any apparatus equipped with a heating mechanism, such as a melt kneader, can be used without particular limitation, and known methods such as a batch method and a continuous method can be employed.

  The atmosphere during the conversion of the PAS prepolymer to a high degree of polymerization by heating is preferably a non-oxidizing atmosphere, and is also preferably performed under reduced pressure. Moreover, when it carries out under pressure reduction conditions, it is preferable to make it the pressure reduction conditions after making the atmosphere in a reaction system once non-oxidizing atmosphere. Thereby, it is in the tendency which can suppress generation | occurrence | production of undesirable side reactions, such as a crosslinking reaction and a decomposition reaction between PAS prepolymers, between PAS produced | generated by heating, and between PAS and a PAS prepolymer. The non-oxidizing atmosphere is an atmosphere in which the oxygen concentration in the gas phase in contact with the PAS component is 5% by volume or less, preferably 2% by volume or less, more preferably an oxygen-free atmosphere, that is, nitrogen, helium, argon or the like. This indicates an inert gas atmosphere, and among these, a nitrogen atmosphere is particularly preferred from the viewpoint of economy and ease of handling. The reduced pressure condition means that the reaction system is lower than atmospheric pressure, and the upper limit is preferably 50 kPa or less, more preferably 20 kPa or less, and even more preferably 10 kPa or less. An example of the lower limit is 0.1 kPa or more, and 0.2 kPa or more is more preferable. When the decompression condition exceeds the preferable upper limit, an undesirable side reaction such as a crosslinking reaction tends to easily occur. It tends to evaporate easily.

  The conversion of the PAS prepolymer to a high degree of polymerization can also be performed in the presence of a fibrous substance. Here, the fibrous substance is a thin thread-like substance, and an arbitrary substance having a structure elongated like a natural fiber is preferable. By converting the PAS prepolymer to a high polymerization degree in the presence of the fibrous substance, a composite material structure composed of PAS and the fibrous substance can be easily prepared. Since such a structure is reinforced by a fibrous material, it tends to have superior mechanical properties, for example, compared to the case of PAS alone.

  Here, among the various fibrous materials, it is preferable to use reinforcing fibers made of long fibers, which makes it possible to highly reinforce PAS. In general, when creating a composite material structure composed of a resin and a fibrous substance, the resin and the fibrous substance tend to become poorer due to the high viscosity when the resin is melted. In many cases, composite materials cannot be produced or expected mechanical properties do not appear. Here, wetting is the physical state of the fluid material and the solid substrate so that substantially no air or other gas is trapped between the fluid material such as a molten resin and the solid substrate such as a fibrous compound. Means there is good and maintained contact. Here, the lower the viscosity of the fluid substance, the better the wetting with the fibrous substance. Since the viscosity of the PAS prepolymer of the present invention when melted is significantly lower than that of a general thermoplastic resin such as PAS, the wettability with the fibrous material tends to be good. After the PAS prepolymer and the fibrous material form good wetting, the PAS prepolymer is converted into a high degree of polymerization according to the PAS production method of the present invention, so that the fibrous material and the high degree of polymerization (polyarylene) It is possible to easily obtain the composite material structure in which the sulfide is formed with good wetting.

As described above, it is preferable that the fibrous material is a reinforcing fiber composed of long fibers, and the reinforcing fiber used in the present invention is not particularly limited. However, as the reinforcing fiber suitably used, generally, a high-performance reinforcing fiber is used. And fibers having good heat resistance and tensile strength. For example, the reinforcing fiber includes glass fiber, carbon fiber, graphite fiber, aramid fiber, silicon carbide fiber, alumina fiber, and boron fiber. Among these, carbon fiber and graphite fiber, which have good specific strength and specific elastic modulus and have a great contribution to weight reduction, can be exemplified as the best. Any type of carbon fiber or graphite fiber can be used as the carbon fiber or graphite fiber depending on the application, but high strength and high elongation carbon having a tensile strength of 450 kgf / mm ² and a tensile elongation of 1.6% or more. Fiber is most suitable. In the case of using long fiber-like reinforcing fibers, the length is preferably 5 cm or more. In the range of this length, it becomes easy to sufficiently develop the strength of the reinforcing fiber as a composite material. Carbon fibers and graphite fibers may be used in combination with other reinforcing fibers. Moreover, the shape and arrangement | sequence of a reinforced fiber are not limited, For example, even if it is a single direction, a random direction, a sheet form, a mat form, a textile form, and a braid form, it can be used. In particular, for applications that require high specific strength and high specific modulus, an array in which reinforcing fibers are aligned in a single direction is most suitable, but it is a cloth (woven fabric) that is easy to handle. Arrangements are also suitable for the present invention.

  The conversion of the PAS prepolymer to a high degree of polymerization can also be performed in the presence of a filler. Examples of the filler include non-fibrous glass, non-fibrous carbon, and inorganic fillers such as calcium carbonate, titanium oxide, and alumina.

  The present invention will be described more specifically with reference to the following examples. These examples are illustrative and not limiting.

<Measurement of melting peak temperature and heat of fusion>
The thermal properties of the cyclic PAS were measured using a Perkin Elmer DSC7. The following conditions were used in the measurement.
・ 50 ℃ × 1min Hold ・ Raise the temperature from 50 ℃ to 360 ℃, Heating rate 20 ℃ / min (The peak temperature in this endotherm is the melting peak temperature. Also, the melting peak area is required for melting. Calculate the heat of fusion.)
・ 360 ℃ × 1 minute hold ・ Temperature drop from 360 ℃ to 100 ℃, temperature drop rate 20 ℃ / min

<Measurement of composition of cyclic polyphenylene sulfide>
The ratio of cyclic polyphenylene sulfide having a different number of repeating units contained in cyclic polyphenylene sulfide was subjected to qualitative quantitative analysis using HPLC. The measurement conditions for HPLC are shown below.
Apparatus: Shimadzu Corporation LC-10Avp series Column: Mightysil RP-18 GP150-4.6 (5 μm)
Detector: Photodiode array detector (UV = 270 nm)

  Moreover, the qualitative analysis of each peak divided into components by the above HPLC measurement is performed from mass spectral analysis of the component divided components, molecular weight information of each component divided by preparative chromatography by MALDI-TOF-MS and GPC. Qualification up to 12-mer was performed.

<Molecular weight measurement>
The molecular weight of cyclic PAS was calculated in terms of polystyrene by gel permeation chromatography (GPC), which is a type of size exclusion chromatography (SEC). The measurement conditions for GPC are shown below.
Equipment: Senshu Science SSC-7100
Column name: Senshu Science GPC3506
Eluent: 1-chloronaphthalene detector: differential refractive index detector Column temperature: 210 ° C
Pre-constant temperature: 250 ° C
Pump bath temperature: 50 ° C
Detector temperature: 210 ° C
Flow rate: 1.0 mL / min
Sample injection amount: 300 μL (slurry: about 0.2% by weight).

[Reference Example 1]
Here, an example in which a cyclic polyarylene sulfide having a melting peak in DSC measurement and having a calorific value of fusion exceeding 20 J / g was prepared by the method disclosed in International Publication No. WO2007 / 034800. Show.

  In a stainless steel reactor 1 equipped with a stirrer, 1169 kg (10 kmol) of 48% aqueous sodium hydrosulfide solution, 841 kg (10.1 kmol) of 48% aqueous sodium hydroxide solution, N-methyl-2-pyrrolidone (hereinafter sometimes abbreviated as NMP) ) Is charged with 1983 kg (20 kmol) and 50% sodium acetate aqueous solution 322 kg (1.96 kmol), gradually heated to about 240 ° C. over about 3 hours while flowing nitrogen at normal pressure, and 1200 kg of water and 26 kg of NMP was distilled off. In addition, 0.02 mol of hydrogen sulfide per 1 mol of the sulfur component charged during this liquid removal operation was scattered out of the system.

  Subsequently, after cooling to about 200 degreeC, the content was transferred to the stainless steel reactor 2 with another stirrer. The reactor 1 was charged with 932 kg of NMP, the inside was washed, and the washing liquid was transferred to the reactor 2. Next, 1477 kg (10.0 kmol) of p-dichlorobenzene was added to the reactor 2, sealed under nitrogen gas, and heated to 200 ° C. with stirring. Next, the temperature was raised from 200 ° C. to 270 ° C. at a rate of 0.6 ° C./min, and held at this temperature for 140 minutes. While 353 kg (19.6 kmol) of water was injected over 15 minutes, the mixture was cooled to 250 ° C. at a rate of 1.3 ° C./min. Thereafter, it was cooled to 220 ° C. at a rate of 0.4 ° C./min, and then rapidly cooled to about 80 ° C. to obtain a slurry (A).

  This slurry (A) was diluted with 2623 kg of NMP to obtain a slurry (B). The slurry (B) heated to 80 ° C. was filtered through a sieve (80 mesh, opening 0.175 mm) to obtain a granular PPS resin containing the slurry as a mesh-on component, and a slurry (C) as a filtrate component.

  1000 kg of the slurry (C) was charged into a stainless steel reactor, and the inside of the reactor was replaced with nitrogen. Then, the mixture was treated at 100 to 150 ° C. under reduced pressure for about 1.5 hours with stirring to remove most of the solvent.

  Next, 1200 kg of ion-exchanged water (1.2 times the amount of slurry (C)) was added, and the mixture was stirred at about 70 ° C. for 30 minutes to form a slurry. The slurry was filtered to obtain a white solid. Add 1200 kg of ion-exchanged water to the obtained solid, stir again at 70 ° C. for 30 minutes, re-slurry in the same way, and after filtration, dry at 120 ° C. in a nitrogen atmosphere, and then dry under reduced pressure at 80 ° C. 11.6 kg of product was obtained.

  From the absorption spectrum in the infrared spectroscopic analysis of the solid, it was found that the solid was a polyphenylene sulfide mixture composed of phenylene sulfide units. As a result of performing GPC measurement of this polyphenylene sulfide mixture and analyzing the chromatogram, the weight fraction of the component having a molecular weight of 5000 or less was 39%, and the weight fraction of the component having a molecular weight of 2500 or less was 32%.

  10 kg of the polyphenylene sulfide mixture obtained above was collected, and 150 kg of chloroform was used as a solvent, and the mixture was stirred for 1 hour under reflux at normal pressure to bring the polyphenylene sulfide mixture into contact with the solvent. Subsequently, solid-liquid separation was carried out by hot filtration to obtain an extract. After adding 150 kg of chloroform to the solid matter separated here and stirring for 1 hour under reflux at normal pressure, solid-liquid separation was similarly performed by hot filtration to obtain an extract, which was mixed with the previously obtained extract. . The obtained extract was in the form of a slurry partially containing solid components at room temperature.

  By treating this extract slurry under reduced pressure, a portion of chloroform was distilled off until the weight of the extract reached about 40 kg to obtain a slurry. Next, this slurry mixture was added dropwise to 600 kg of methanol with stirring. The resulting precipitate was filtered to recover the solid content, and then dried under reduced pressure at 80 ° C. to obtain 3.0 kg of white powder.

    From the absorption spectrum in the infrared spectroscopic analysis of this white powder, it was confirmed that the white powder was a compound composed of phenylene sulfide units. Moreover, this white color is obtained from mass spectrum analysis of components separated by high performance liquid chromatography (apparatus; LC-10, manufactured by Shimadzu Corporation, column; C18, detector; photodiode array), and molecular weight information by MALDI-TOF-MS. The powder is a mixture mainly composed of cyclic polyphenylene sulfide having 4 to 12 repeating units, and the weight fraction of the cyclic polyphenylene sulfide is about 94%, and about 6% is a linear polyphenylene sulfide oligomer and the number of repeating units. It was a mixture of 13 or more cyclic polyphenylene sulfides. From the above analysis results, it was found that the white powder obtained above was cyclic polyarylene sulfide containing 50% by weight or more of cyclic polyarylene sulfide. Hereinafter, this white powder is referred to as cyclic PAS mixture 1.

  From the analysis of the HPLC measurement result of the cyclic PAS mixture 1, the cyclic PAS contained in the cyclic PAS mixture 1 was repeated when the total amount of cyclic PAS having 4 to 12 repeating units was 100%. The proportions of cyclic PAS with 5, 6, 7 and 8 units were found to be 12%, 13%, 28% and 15%, respectively. As a result of GPC measurement, it was found that the weight average molecular weight was 900, and no component having a molecular weight of 2500 or more was contained.

  Moreover, as a result of DSC measurement of the cyclic PAS mixture 1, it was found that the melting peak temperature was 217 ° C. and the heat of fusion was 28 J / g.

[Example 1]
About 5 g of cyclic PAS mixture 1 having a heat of fusion exceeding 20 J / g obtained in Reference Example 1 was charged into a glass container equipped with a stirrer. While the stirring was stopped, the atmosphere in the flask was replaced with nitrogen, and then the flask was set in a mantle heater that had been temperature-controlled in advance and heated. About 3 minutes after the start of heating, a part of the contents began to liquefy, so stirring was started. The internal temperature reached about 280 ° C. about 10 minutes after the start of heating. At this stage, the content was a transparent, uniform liquid and no solid content was observed. After reaching 280 ° C., the mixture was held for 5 minutes with stirring, and then the mantle heater was removed, stirring was stopped, and the mixture was cooled to room temperature over about 1.5 hours.

  As a result of DSC measurement of the obtained solid, no melting peak was observed, and it was found that amorphous cyclic PAS was obtained. As a result of HPLC measurement, the content of cyclic PAS having 4 to 12 repeating units contained in the obtained amorphous cyclic PAS was 94%, and no difference from that before heating was observed. Also, no difference from the cyclic PAS mixture 1 before heating was observed in the GPC measurement.

[Example 2]
The same operation as in Example 1 was performed except that the holding time after reaching 280 ° C. was 1 minute.

  As a result of DSC measurement of the obtained solid material, a minute melting peak was confirmed at 248 ° C., but it was found that the heat of fusion was very small, 2 J / g, and an almost amorphous cyclic PAS was obtained. I found out. As a result of HPLC measurement, the content of cyclic PAS having 4 to 12 repeating units contained in the obtained amorphous cyclic PAS was 94%, and no difference from that before heating was observed. Also, no difference from the cyclic PAS mixture 1 before heating was observed in the GPC measurement.

[Example 3]
The same procedure as in Example 1 was performed except that the heating temperature was 260 ° C.

  As a result of DSC measurement of the obtained solid, a melting peak was confirmed at 244 ° C., but the heat of fusion was 8 J / g, which was found to be significantly reduced compared to before heating. As a result of HPLC measurement, the content of cyclic PAS having 4 to 12 repeating units contained in the obtained amorphous cyclic PAS was 94%, and no difference from that before heating was observed. Also, GPC measurement showed no difference from the cyclic PAS mixture 1 before heating.

[Example 4]
The same operation as in Example 1 was performed except that the heating temperature was 300 ° C.

  As a result of DSC measurement of the obtained solid, a melting peak was observed at 247 ° C., and the heat of fusion was 2 J / g. Moreover, as a result of HPLC measurement, the content of cyclic PAS having 4 to 12 repeating units contained in the obtained amorphous cyclic PAS was 92%, which was 2% lower than before heating. all right. Further, in GPC measurement, a slight peak was observed at a peak molecular weight of about 50,000. Under these conditions, it was found that the ring-opening polymerization of the cyclic PAS proceeded slightly to produce a high molecular weight linear PAS.

[Comparative Example 1]
Here, an example in which the heating temperature of the cyclic PAS is the melting peak temperature of the raw material cyclic PAS is shown.

  The same procedure as in Example 1 was performed except that the heating temperature was 200 ° C. In this case, the content was an opaque and non-uniform slurry from the time of reaching 200 ° C. to the end of holding at 200 ° C.

  As a result of DSC measurement of the obtained solid, a melting peak was observed at 238 ° C., and the heat of fusion was found to be 22 J / g.

  As is clear from the examples and this comparative example, it can be seen that when the temperature at which the raw material cyclic PAS is heated is equal to or lower than the melting peak temperature, a cyclic PAS having a heat of fusion of 20 J / g or less cannot be obtained.

Claims (8)

A cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide represented by the general formula (1), wherein the heating rate is 20 ° C. from 50 ° C. to 360 ° C. using a differential scanning calorimeter (DSC). A cyclic polyarylene sulfide having a heat of fusion of 20 J / g or less as measured at / min.

(M is an integer of 4 to 50. m may be a mixture of 4 to 50) 2. The cyclic polyarylene sulfide according to claim 1, wherein the content of cyclic PAS of m = 6 with respect to the cyclic polyarylene sulfide contained in the cyclic polyarylene sulfide mixture is less than 50% by weight. When the total amount of cyclic polyarylene sulfides of general formula (1) where m is 4 to 12 in the cyclic polyarylene sulfides contained in the cyclic polyarylene sulfide mixture is 100%, m is a ring of 5 to 8 The cyclic polyarylene sulfide according to claim 1 or 2, comprising 5% or more of each of the formula polyarylene sulfides. The heat of fusion when measured at 50 ° C / min from a temperature of 50 ° C to 360 ° C with a differential scanning calorimeter (DSC) is 10 J / g or less. The cyclic polyarylene sulfide described. 4. The melting peak is substantially not observed when measured with a differential scanning calorimeter (DSC) from 50 ° C. to 360 ° C. at a heating rate of 20 ° C./min. The cyclic polyarylene sulfide described. A cyclic polyarylene sulfide mixture containing 50% by weight or more of the cyclic polyarylene sulfide represented by the general formula (1), wherein the temperature rising rate is 50 ° C. to 360 ° C. with a differential scanning calorimeter (DSC) 20 6. The cyclic polyarylene sulfide mixture having a heat of fusion of more than 20 J / g when measured at ° C./min is heated after its melting peak temperature or higher and then cooled. A process for producing cyclic polyarylene sulfide. The method for producing a cyclic polyarylene sulfide according to claim 6, wherein a reduction rate of the cyclic polyarylene sulfide content contained in the cyclic polyarylene sulfide mixture is 10% or less before and after heating. The method for producing a cyclic polyarylene sulfide according to claim 6 or 7, wherein the upper limit temperature of heating is 320 ° C or lower.